Cylindrical lithium rechargeable battery and method for fabricating the same

Abstract

A cylindrical lithium rechargeable battery has an anode tab that is welded to a lower surface of a cylindrical case through laser welding. The cylindrical lithium rechargeable battery includes a cylindrical electrode assembly formed at a center portion thereof with a space section and including a cathode plate, an anode plate, a separator interposed between the cathode plate and the anode plate, a cathode tab that is coupled with an end of the cathode plate, and an anode tab that is coupled with an end of the anode plate. The battery also comprises a cylindrical case including a cylindrical sidewall that forms a space to receive the cylindrical electrode assembly therein and a lower wall that is provided at a bottom of the cylindrical sidewall and a cap assembly that is coupled with an upper portion of the cylindrical case and has a terminal section that is coupled with the cylindrical electrode assembly. In addition, a center pin is installed in the space section of the cylindrical electrode assembly, wherein the anode tab is coupled with an inner center portion of the lower wall of the cylindrical case by laser welding.

Description

CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims priority to and the benefit of Korean Patent Application No. 2004-0048304 filed on Jun. 25, 2004, which is hereby incorporated by reference for all purposes as if fully set forth herein. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a cylindrical lithium secondary battery and a method of fabricating the same. In particular, the present invention relates to a cylindrical lithium secondary battery and a method of fabricating the same, in which an anode tab is welded to a lower surface of a cylindrical case by laser welding. [0004] 2. Description of the Prior Art [0005] Recently, various portable lightweight and compact electronic devices such as cellular phones, notebook computers, and camcorders have been actively developed and produced. These devices are equipped with a battery pack that may include at least one rechargeable battery that is capable of outputti...

AI Technical Summary

Problems solved by technology

If a cathode tab is coupled with the lower end of the cylindrical case by resistance welding, the electrodes must be exchanged frequently which increases the manufacturing time for rechargeable batteries and may increase when producing a large amount of rechargeable batteries.

In addition, in resistance welding, welding energy is gradually transferred from a welding surface to a peripheral portion of an object to be welded such that the welding bond may have uneven welding strength.

Furthermore, impurities may result or a spark may occur during the resistance welding process which may cause damage to the electrode assembly.

Images